Illuminated dial



March 19, 1935. Q w HQFFR|TZ 1,994,950

ILLUMINATED DIAL Filed March 24, 1934 2 Sheets-Sheet 1 Y P MM March 19,1935. c. w. HOFFRITZ 1,994,950

ILLUMINATED DIAL Filed March 24, 1934 2 Sheets-Sheet 2 NTOR 1 $2444 /%%WW Patented Mar. 19, 1935 UNITED STATES PATENT OFFICE ILLUMINATED DIALCalif.

Application March 24;

4 Claims.

6 a simple and inexpensive illuminated dial having a hand, or handsthereon, in which the hands and/or numerals on the dial are unusuallylegible, both when not self-illuminated and viewed by daylight, and whenself-illuminated at night.

Another object is to provide a dial having an indirectly illuminatedhand or numerals or both, which appear to be in themselves sources ofillumination.

I achieve the foregoing objects, in a clock, by providing. in a clockdial case, a dial painted black and bearing white hour numerals andcarrying white hour and minute hands, and a neon tube so shaped andlocated in the case as to be invisible when the dial is viewed byobservers, the shape of the hour and minute hands being such withrespect to the neon tube, and the neon tube being arranged in such amanner with respect to the numerals painted white upon the dial thatwhen the neon light is turned on, streams of colored light will engageacross the face of the dial and will impart their color upon the whitenumerals as well as upon the hour and minute hand without coloring anyother part of the displayed surface of the dial. In this manner duringdaytime the white numerals and white clock hands are clearly visible,and at night they are rendered visible alone as the other parts of thedial are black in appearance, and they are readily distinguishable dueto the intense colors imparted to them by the colored rays of neonlight.

Furthermore, I prefer in accordance with the invention, to construct thehour and the minute hand so as to have longitudinally extendingoppositely inclining angular walls, providing reiiectory surfaces, sothat these angular walls of each hand, in any and all radial positionsit occupies on the dial, are exposed to colored light reflectionsemanating from a circular neon tube concealed out of sight from in frontof the dial and received by a glass pane in a cover closing the dialcase. The reflected rays of light coming from the tube fall upon theface of the dial but since the numerals and the clock hands alone arewhite, the remaining surface of the dial being black, these numerals andthese clock hands receive the reflected rays of light which impart theircolor to the same. The colored rays show to the best advantage upon theangular sides of 1934, Serial No. 717,200

the clock hands for there is a maximum absence of shadows here. Theresult is a clock dial the readable parts of which, at night, are highlycolored artificially by means of colored light only which may be causedto disappear during the daytime, but when the light is on, the sourcethereof is unobservable by readers of inscriptions on the dial.

With the above and other objects in view, my invention consists in thecombination, arrangement and details of construction disclosed in thedrawings, and specification, and then more particularly pointed out inthe appended claims.

In the drawings, which are merely illustrative of my invention and inwhich similar reference characters designate similar parts through therespective views:

Figure 1 is a front view of a clock in accordance with my invention,with the glass pane removed,

Figure 2 is a front view of a minute hand constructed in accordance withmy invention,

Fig. 2a is a cross section of the hand shown in Fig. 2, the sectionbeing taken in the plane Ila-41a of Fig. 2,

Figure 3 is a front view of the clock, with the cover removed, showingthe neon tube arranged thereon,

Figure 4 is a side view of the hour hand,

Figure 5 is a side view of the clock case, showing the cover and neontube in cross section,

Figure 6 is a side view of the clock case, showing the cover and neontube in vertical section, and

Figure 7 is a perspective view of the under side of the hour hand.

I will now describe my invention in detail. The conventional clock caseis designated 10 and is closed at its front and back, the outer annularpart 11 thereof being formed, if need be, with an annular groove or seat12, in which an annular cover or cover member 13 is designed to seat.The base 14 of the annular cover ilts snugly into the annular seat 12 ofthe clock case, the outer face of the cover being designated 16. Thecover has a bead 17 forming also an annular seat, and in this annularseat is mounted a glass panel 19, designed to close the usual opening inthe front of the cover. It will be seen that cleats 20 may confine thetransparent or glass panel 19 in position within the bead 17 of thecover. It will be further seen that suitable detachable fasteners 21 aredesigned to secure the cover in place on the clock case.

The clock dial is designated 22 and it has a circumferential series ofwhite hour numerals 23, with white markings 24 appearing radially ofthese numerals and marginally of the dial 22. There are also minutemarkings, four in number, designated 25 and appearing between the whitemarkings 24, as shown in Figure 1. There is the usual minute arbor 27 ofthe clock or timepiece, and the hour arbor 26 thereof, it beingunderstood that my invention is preferably located in an electric clock.

The hour hand and minute hand may each consist of an innermost baseportion made preferably of flat metal and having a longitudinal stemwhose surface is made into oppositely inclined elongated walls, so thatthe stem is sub-' stantially V-shape in cross section as shown in Figure2a. Thus the base portion of the minute hand is designated 28, while itsoppositely in-- clined walls or sides are designated 31, 32, and thebase portion of the hour hand is designated 29 and its oppositelyinclined sides or'walls are designated 31, 32 respectively. The baseportions of both hands are operatively mounted upon the respective hourand minute arbors of the clock. It will be seen from Figure 1 that thereis a pull chain switch 33 for opening and closing the circult to theneon source of light, about to be described, and that a flexibleconductor cord extends into the case, and is designated in Figure 1, at34.

A circular neon tube 35 is spaced in parallel relation with respect tothe outer face of the dial 22, being mounted upon anchors 36 of approveddesign which anchors are secured to the outer wall of the case. It willbe seen that the clock case forward wall is formed with a pair ofcontiguous sockets 38, into which the opposing ends of the neon tube,after being bent, extend as at 39.

It is to be noted that when the cover has been fixedly secured upon theclock case that the various parts will have the following positions. Theneon tube35 will be seated so as to be directly in the annular seat 15of the cover, the circular portion of this tube being of a diameterlarger than the head 17 of the cover so when an observer views the dialfrom outside of the glass pane 19 he cannot see this neon tube at all.

The neon tube is spaced in back of the glass panel 19, but is spaced infront of the hour and minute hand and in front of the dial 22. Duringdaylight an observer can see the numerals 23 on the dial readily andconspicuously because they are painted white and show up clearlyagainst.

the opaque, black background of the dial 22. He also can see the hourand minute hands just as clearly since they too are painted white. I Theblack background afiorded by the dial at all points of its displaysurface except where the painted white numerals and markings appear alsoserves the useful purpose at night of providing a field of colored lightillumination upon the dial.

When the circuit is closed to the .neon tube 35, by means of the pullchain 33, the neon emits rays of intense colored light, and streams ofcolored artificial light emanate from all points in the surface of thecircular tube 35, impinging upon the irmer surface of the glass panel 19and naaasso being by the latter reflected back directly upon the dial22, and the rays of colored light assume a direction or path ofprojection across the face of the dial from all radial directions fromthe marginal edge of the dial towards the center thereof. The entireeflective display surface of the dial 22 becomes sufiused with rays ofcolored light, and the light will color the numerals and markings on thedial brilliantly changing the whiteness of these numerals and markingsto this color. The rays of light will also be difiused in the directionof, so as to fall upon the oppositely inclined elongated walls 31, 32 ofeach clock hand 28, and 29 respectively, and as shown particularly inFigure 6 the rays of colored light reflected from the glass pane 19 willsuiiuse these sides with colored lights without the presence of a shadowdue to the, oblique disposition of each wall 31, or 32 with respect tothe vertical disposition of the glass panel 19. In any radial positionassumed by the inclined sides of either clock hand, streams of lightfrom the concealed neon tube will be reflected upon same, so that inthis manner the entire face of the indicating portions of the hands willbe colored. The dial being dark at night except where the colorednumerals and hands are concerned. the latter are conspicuously displayedupon the dial at night and can be read at very great distances.

I intend to cover all variations falling within scope of claims.

What I claim and seek protection on by Letters Patent is:-

1. In combination, a case provided with a dial constituting a darkbackground, contrasting light-difiusive numerals and a hand, said handbeing beveled, a luminous gas tube surrounding and spaced outwardly asuitable distance from the dial, and a reflecting ring in front of andconcealing the gas tube from'the front of said case.

2. A clock case provided with a dial constituting a dark background,contrasting light-difiusive numerals and hands, said hands beingbeveled, a luminous gas tube surrounding and spaced outwardly a suitabledistance from the clock dial, a reflecting ring in front of andconcealing the gastube from the front of the clock, and a glass panelsupported by said ring and located in front of and covering the clockdial.

3. In combination, a case provided with a dial constituting a darkbackground, contrasting lightdifiusive-numerals and a hand, a luminousgas tube surrounding and spaced outwardly a suitable distance from thedial and hand, a refleeting ring in front of and concealing the gas tubefrom the front of said case, and a glass panel supported by said ringand located in front'of and covering the dial. a. A clock case providedwith a dial constituting a dark background, contrasting light-diffusivehands, a luminousgas tube surrounding and spaced outwardly asuitabledistance from the clock dial, a reflecting ring in front of andconcealing the gas tube from the front of the clock, and a glass panelsupported by said ringand located in front of and covering the clockdial.

' CHARLES HOITTRITZ.

